A process control system normally comprises a number of process control devices involved in the control of the process.
The process control system does then typically comprise control computers as well as operator stations or monitoring computers via which operators can monitor the process. The operator stations are then normally stationary and provided in a control room or a control station in the plant.
At an operator station in a process control system it is common to have a graphical process control view displaying the process or a part of the process, where the process and its devices may be represented as graphical blocks interconnected in a logical structure.
It is also known to have video cameras installed at locations around the process control devices. The cameras capture video images that are streamed to the control room or control station for being observed via the monitoring computers. The operators can then view the video streams on the screens of their monitoring computers. However, in this case the video is typically displayed beside the graphical blocks. The majority of the display area is typically occupied by the graphical process control view.
In some processes the overview is much better in the video stream. This means that in the above-mentioned situation, it is possible that an operator fails to notice important changes of the process because the video is dominated by the process view. It would thus be of interest to get a better overview of the process where a live video stream dominates the user interface display. However, it may still be necessary to see the process view.
It is known to overlay process control graphics on live video in a process control environment. This is described in US 2013/0321245. However, the overlaying is in this document performed in a mobile device. Furthermore it seems as the display of the process control graphics relies on the mobile device being brought out to the location where the video is captured in order to obtain knowledge of the process graphics that are to be combined with the live video. The teachings of this document cannot therefore easily be transferred to an environment where the user interface is stationary.
There is thus a need for allowing a better overview of a process control system at a stationary user interface.
The present invention is provided for solving one or more of the above described problems.